Don't set aside one point to make another (3)
I believe the answer is:
dot
'don't set aside one point' is the definition.
The definition suggests a singular noun which matches the answer.
'make another' is the wordplay.
I cannot really see how this works, but
'make' could be 'do' (do can mean to make or prepare) and 'do' is located in the answer.
A single letter 't' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'to' acts as a link.
(Other definitions for dot that I've seen before include "Cotton, say" , "Flyspeck: period in a web address" , "Internet punctuation mark" , "Long-ago year?" , "Little mark" .)